Better together... we deliver SASOL CHEMICALS BASE CHEMICALS (EXPLOSIVES) MOSH - "Day of Learning"...
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Transcript of Better together... we deliver SASOL CHEMICALS BASE CHEMICALS (EXPLOSIVES) MOSH - "Day of Learning"...
better together ... we deliver
SASOL CHEMICALS
BASE CHEMICALS (EXPLOSIVES)
MOSH - "Day of Learning"2014
better together ... we deliver
Copyright ©, 2014, SasolConfidential
2
Topic:
Energy partitioning / sequential firing and the use thereof – ‘back to basics’
better together ... we deliver
Copyright ©, 2014, SasolConfidential
Eliminating falls of ground
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Define the requirements
• Define the problem and determine what is to be achieved?
• Identify how it is to be achieved and keep it simple
Improve blasting results, safely
better together ... we deliver
Copyright ©, 2014, SasolConfidential
Eliminating falls of ground
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Define the hazard – common reasons for ‘falls of ground’
Natural
• Geological discontinuities
• Rock bursts
Planning
• Mining method• Mine discipline• Support or roof
bolting not effective
Training
• Knowledge of workers
• Barring or scaling• Blasting• Incorrect use of
equipment
better together ... we deliver
Copyright ©, 2014, SasolConfidential
PlantLoading & hauling
Priming, Charging &
Blasting
Eliminating falls of ground
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Define the hazard – interaction of everybody to address ‘falls of ground’
Plan for improvements in ‘falls of ground’ & accurately execute blast design
DrillingExcavation preparationSurveyPlanningGeology
Plan:
blast design
Do:
departmental performance
Measure:
each department
in value chain
Review & Improve
Are you prepared to change?
better together ... we deliver
Copyright ©, 2014, SasolConfidential
Eliminating falls of ground
6
Define the requirements – ‘falls of ground’ are influenced by
• Energy / Energy / Energy
Energy Distribution• Location of hole -
marking• Hole diameter• Burden and spacing• Careful
implementation of drill pattern
• Directionality of drilling
Available Energy• Correct amount and
type of explosives for required for specific conditions
• Manage site sensitivity - geology
• Evaluate energy for special conditions – poor floor, large toe burdens, geology
Release of Energy• Control & ensure the
‘path of least resistance’
• Correct use stemming – containment of energy
• Blast holes loaded according to geology
• Match timing to existing field conditions – wet, fractured
• Accurate delays
better together ... we deliver
Copyright ©, 2014, SasolConfidential
Product selection
7
Plan – Do – Measure - Review
Initiation control Explosive energy
Output of rockPhysical effort
Detonationand Energy
Release
starter
initiation devices
explosives
wastedenergy
cast
damage
fragmentation
BLASTING PROCESS
RESULTPREPARATION
loading / cleaning / hauling
Charging-upand
Stemming
Geology, Standardsand Support
preparation
marking
drilling
better together ... we deliver
Copyright ©, 2014, SasolConfidential
Blast optimisation
8
Quality ultimately equals quantity
• The objectives of any blast is:• Maximum advance per blast• Minimise surrounding rock damage• Minimise the effort • Reduce overall costs (explosives & accessories, time, drilling)• Maximise the yield
Effective relief = maximum advance with minimal perimeter damage (‘falls of ground’ reduction)
36.0cm (advance) = 1.0cm (relief required)
ADVANCE IS NOT DETERMINED BY THE SIZE OF THE EXCAVATION!
better together ... we deliver
Copyright ©, 2014, SasolConfidential
Blast optimisation
9
Relief + accuracy + correct level of energy = competent perimeter results
36.0cm (advance) = 1.0cm (Ø relief hole) Relief hole determination with an 38.0mm drill bit
Therefore if 3.2m advance / blast is required = 5.49 holes required
36 x ( ) = 3.2m = 6 holes required
= 8.9cm (minimum relief required 3 holes / optimal results require 6 holes)
1.2m x 1.2m tunnel5.2m advance
4.2m x 4.2m tunnel8.54m advance
better together ... we deliver
Copyright ©, 2014, SasolConfidential
Blast optimisation
10
Reliability + Accuracy = Safety
• Distance of the cut holes from a stab hole
a = hard rock = 1.5
a = soft rock = 2.0
• Delay – one hole at a time
hard rock = 40.0ms / m
soft rock = 60.0ms / m
a = 171 / 190
38 x 6 = 228
better together ... we deliver
Copyright ©, 2014, SasolConfidential
11
Hole distribution & charge efficiency ensures success
• The cut & easers are marked as an equilateral Charge mass = 0.25 to 0.65kg / m
triangle
(base / 1.155) = height charge mass for 3.2m (@ 0.45) = 1.17kg (@ 0.65) = 1.70kg
342/ 1.155 = 296
Blast optimisation
better together ... we deliver
Copyright ©, 2014, SasolConfidential
12
Sequential firing / powder factor &
creating the relief
Blast optimisation
GRADE LINE
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General guide
Cut = 0.4 to 0.6 kg/m
Easers = 0.6 to 0.8 kg/m
Production = 1.40 kg/m
Lifter = 1.40 kg/m
Perimeter = 0.2 to 0.4 kg/m
General guide
Cut = ANFO, emulsion, watergel
Easers = ANFO, emulsion, watergel
Production = ANFO, emulsion, watergel
Lifter = ANFO, emulsion, watergel
Perimeter = ANFO, emulsion, watergel
better together ... we deliver
Copyright ©, 2014, SasolConfidential
13
Blast optimisation
Sequential firing / powder factor & creating the relief
General guide
Cut = 0.6 to 0.8 kg/m
Easers = 0.6 to 0.8 kg/m
Production = 0.6 to 0.8 kg/m
General guide
Cut = ANFO, emulsion, watergel
Easers = ANFO, emulsion, watergel
Production = ANFO, emulsion, watergel
better together ... we deliver
Copyright ©, 2014, SasolConfidential
14
Standard deviation & safety
Accuracy the key to success & sequential firing
Cushion disc
Shock tube
Bushing
Isolation cup
Pyrotechnic delay train
Lead azide primary charge
PETN Base charge
Flatland crimp
Seal crimp
Ø 7.5mm Aluminum cap shell
Cushion DiscDIB
Lead WireEarth Spike
Micro Chip
Moulded grommet CapacitorFuse head
Lead azide primary charge
PETN Base chargeCushion Disc
PC board
better together ... we deliver
Copyright ©, 2014, SasolConfidential
Strategic Partner
Value-Added Supplier
Product Vendor
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Mine need a “One Solution” Value – Added supplier and strategic partner
Risk/RewardSupplier’s value-add
RelationshipsInformation Sharing
Increase
Number of Suppliers FeaturesPrice“Total cost” of selling/buying
Decrease
Current Supply Position
Current relationships are transactional – benefits will only be realised at strategic partner stage.
Mitigation of diamond damage
Slide 16
Questions?